1. Field of the Invention
The present invention relates to a scroll compressor suitable for use in an air conditioning device for an automobile.
2. Description of Related Art
Known in a prior art is a scroll compressor having a center housing in which stationary and movable scroll members are arranged so that compression chambers are formed between the scroll members. A front housing is connected to the center housing. A rotating shaft has a large diameter portion which is rotatably supported in the front housing by means of a radial bearing. An eccentric shaft is fixedly connected to an inner end of the rotating shaft, on which eccentric shaft a movable scroll member is rotatably supported by way of the bushing 6 and a second radial bearing. Furthermore, a mechanism for blocking self-rotation of the movable scroll member is arranged between the front housing and the movable scroll member, so that self-rotation of the movable scroll member about its own axis does not occur. A rotation of the rotating shaft causes the eccentric shaft, which is eccentric to the shaft, to be rotated about the axis of the shaft. Thus, the movable scroll member rotatably supported on the bushing effects an orbital movement about the axis of the shaft, so that the compression chambers are moved radially inwardly, while the volume of the chambers is reduced, thereby compressing the gas in the compression chambers. During the orbital movement, a relative radial movement of the eccentric shaft with respect to the bushing is allowed due to the compression reaction force, thereby obtaining a desired radial contact force between the movable scroll member and the stationary scroll member.
In the prior art scroll compressor, in order to prevent the bushing from being withdrawn from the eccentric shaft, while allowing a relative radial movement between the bushing and the eccentric shaft, a washer is inserted to the eccentric shaft from its free end remote from the large diameter portion of the shaft, and a snap ring is fitted to the shaft and engaged with a groove formed on the eccentric shaft. However, by this construction, an outwardly closed space is created between the eccentric shaft and the bushing. Thus, the lubrication of the sliding portion between the eccentric shaft and the bushing relies only to the lubricant held in the space. Thus, the lubrication of the sliding surfaces is likely to be insufficient.